There has always been a problem in ingressing and egressing into and from the cargo beds of relatively large wheel vehicles whether an oxen cart, a horse drawn wagon, or in more modern time the beds of pickup and similar types of trucks. Even the small or mini pickups which have become popular in recent years have a cargo bed which is between two and a half and three feet off the ground with the four-wheel drive versions in many instances being well in excess of three feet. Standard size pickups average close to three feet in height of the cargo bed with the four-wheel drive versions being on occasions five feet or more in height.
Although these relatively high heights of cargo beds are quite often convenient to load, they are very difficult to ingress and egress into and from.
All standard pickup trucks include tailgates which fold down from vertical to horizontal positions with the horizontal position effectively being an outward extension of the cargo bed and thus disposed at the same height above the ground as such bed. Whether ingressing and egressing a camper disposed within the pickup bed, or to adjust cargo, or for whatever other reason, two to two and a half feet is a large step with three feet or better being extremely difficult if not impossible to accomplish unless the person climbs instead of steps into the truck.